<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>三行display:table</title>
    <style>
        html,body,div{
            margin: 0;
            padding: 0;
        }
        html,body{
            height: 100%;
            width: 100%;
        }
        .first{
            display: table;
            width: 100%;
            height: 100%;
            
        }
        .first > div{
            display: table-row;
        }
        .one{
            height: 100px;
            background: firebrick;
        }
        .two{
            height: 100%;
            background: palevioletred;
        }
        .three{
            height: 100px;
            background: hotpink;
        }
    </style>
</head>
<body>
    <!-- 三行布局 -->
    <!-- 第一种，使用display：table-->
   <div class="first">
    <div class="one">one</div>
    <div class="two">two</div>
    <div class="three">three</div>
   </div>
</body>
</html>
<!-- 必须注意：模拟成表格之后，必须要有内容，才会出现效果？？？ -->